<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Service_Amazon
 * @subpackage Ec2
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: Response.php 16971 2009-07-22 18:05:45Z mikaelkael $
 */

require_once 'Zend/Http/Response.php';

/**
 * @category   Zend
 * @package    Zend_Service_Amazon
 * @subpackage Ec2
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_Service_Amazon_Ec2_Response {
	/**
	 * XML namespace used for EC2 responses.
	 */
	protected $_xmlNamespace = 'http://ec2.amazonaws.com/doc/2009-04-04/';

	/**
	 * The original HTTP response
	 *
	 * This contains the response body and headers.
	 *
	 * @var Zend_Http_Response
	 */
	private $_httpResponse = null;

	/**
	 * The response document object
	 *
	 * @var DOMDocument
	 */
	private $_document = null;

	/**
	 * The response XPath
	 *
	 * @var DOMXPath
	 */
	private $_xpath = null;

	/**
	 * Last error code
	 *
	 * @var integer
	 */
	private $_errorCode = 0;

	/**
	 * Last error message
	 *
	 * @var string
	 */
	private $_errorMessage = '';

	/**
	 * Creates a new high-level EC2 response object
	 *
	 * @param Zend_Http_Response $httpResponse the HTTP response.
	 */
	public function __construct(Zend_Http_Response $httpResponse)
	{
		$this->_httpResponse = $httpResponse;
	}

	/**
	 * Gets the XPath object for this response
	 *
	 * @return DOMXPath the XPath object for response.
	 */
	public function getXPath()
	{
		if ($this->_xpath === null) {
			$document = $this->getDocument();
			if ($document === false) {
				$this->_xpath = false;
			} else {
				$this->_xpath = new DOMXPath($document);
				$this->_xpath->registerNamespace('ec2',
				$this->getNamespace());
			}
		}

		return $this->_xpath;
	}

	/**
	 * Gets the document object for this response
	 *
	 * @return DOMDocument the DOM Document for this response.
	 */
	public function getDocument()
	{
		try {
			$body = $this->_httpResponse->getBody();
		} catch (Zend_Http_Exception $e) {
			$body = false;
		}

		if ($this->_document === null) {
			if ($body !== false) {
				// turn off libxml error handling
				$errors = libxml_use_internal_errors();

				$this->_document = new DOMDocument();
				if (!$this->_document->loadXML($body)) {
					$this->_document = false;
				}

				// reset libxml error handling
				libxml_clear_errors();
				libxml_use_internal_errors($errors);
			} else {
				$this->_document = false;
			}
		}

		return $this->_document;
	}

	/**
	 * Return the current set XML Namespace.
	 *
	 * @return string
	 */
	public function getNamespace()
	{
		return $this->_xmlNamespace;
	}

	/**
	 * Set a new XML Namespace
	 *
	 * @param string $namespace
	 */
	public function setNamespace($namespace)
	{
		$this->_xmlNamespace = $namespace;
	}

}
